Best and Worst Stocks of 2011

By Ben Steverman - 2011-12-14T19:18:53Z

Photograph by Chitose Suzuki/AP

Company Symbol % Change
4 of 23

Biogen Idec Inc.

Industry: Biotechnology

Total return: 68.9 percent

The world's largest maker of medicines treating multiple sclerosis, Biogen Idec (BIIB) saw its biggest share gains of the year -- including a 15 percent rise on Apr. 21 -- driven by studies showing the effectiveness of the experimental MS pill BG-12. Analysts estimated the product could bring in annual sales of as much as $3 billion.